Warnings of dense fog are issued when visibility is expected to fall below 200 metres. Severe disruption to transport occurs when the visibility falls below 50 metres.

  • Avoid travel if possible
  • Drive very slowly with dipped headlights, full-beam lights reflect off the fog causing a ‘white wall’ effect
  • Keep an eye on your speed, fog can give the illusion of moving in slow motion
  • Use fog lights, but remember to turn them off when the visibility improves
  • Don’t hang on the tail lights of the car in front, rear lights can give a false sense of security
  • Watch out for freezing fog which is made of water droplets that freeze on contact with objects such as the pavement, road, car, etc. It can quickly form a layer of ice.